Abstract: The present invention discloses a method for performing accounting of a user by a Remote Authentication Dial-In User Service client (RADIUS), the method comprising, after the user requesting for a session in order to access a network has been authenticated successfully, performing, by the RADIUS client, accounting of the user in accordance with a preset accounting policy of the RADIUS client during the session; carrying, by the RADIUS client, an amount of money consumed by the user during the present session in a Account-of-Session-Cost attribute added in the RADIUS client protocol, and sending the Account-of-Session-Cost attribute, by the RADIUS client, to a RADIUS server after the session has been finished; and updating, by the RADIUS server, information of the user in accordance with the received amount of money consumed by the user during the present session.